Normal Perio Supplemental Flashcards
What makes up the masticatory mucosa?
-keratinized stratified squamous epithelium -Dorsum of tongue, hard palate, and attached gingiva
what is the lining of the mucosa made up of?
-non-keratinized stratified squamous epithelium -buccal mucosa -labial mucosa
what is the specialized mucosa component of the oral mucosa?
- dorsum of the tongue
- taste buds, lingual papillae
which 3 mucosa make up the oral mucosa
-masticatory mucosa -lining mucosa -specialized mucosa
what are 2 histologic features of the masticatory epithelium?
-keratinized -rete pegs (rete processes, rete ridges)
what are rete pegs?
-downward thickening of epidermis between the dermal papillae -they function in helping keratinized tissues resist forces during mastication
what 3 main layers comprise the basement membrane?
-basal lamina -attaching proteins -lamina reticularis
the basal lamina consists of the lamina lucida and lamina densa. what are the main molecules in each layer?
lamina lucida: -laminin -integrins -entactins -dystroglycans lamina densa: -collagen IV
what two proteins make up the attaching proteins of the basement membrane?
-collagen VII -fibrillin
what makes up the lamina reticularis of the basement membrane
-collagen III
what are langerhans cells?
antigen-presenting cells that are important for immune system functions
what 4 main components make up the peridontium?
-gingiva -cementum -periodontal ligament -alveolar supporting bone
what are 3 types of gingiva?
-attached -unattached (margina, free) -interdental
T or F: periodontal tissues are biologically interdependent and withstand changes with age and disease.
false: they are subject to variations and changes with age and disease
what 4 tissues does the periodontium NOT include?
-enamel -dentin -pulp -surrounding bone of the alveolar process
what are the 5 main functions of the periodontium?
-attach -resist -maintain -adjust -defend
describe characteristics of periodontium functions
- tooth support
- shock absorber: withstand forces of mastication
- sensory receptor necessary for proper positioning of the jaw
- nutritive: blood vessels provide the essential nutrients to the vitality of the PDL
what are 5 components of the gingival epithlium?
-keratinocytes -desmosomes -tonofilaments -basal lamina -hemidesmosomes
4 anatomical areas of the gingiva
-free gingiva (marginal) -gingival sulcus -interdental gingiva (papilla) -attached gingiva
what is the difference between the gingival sulcus and the periodontal pocket?
-gingival sulcus implies health -periodontal pocket implies disease
what are the gingival boundaries?
-upper (coronal) edge is the gingival margin -lower (apical) edge is the alveolar mucosa
Name these tissues:
what part of the gingival sulcus does the free gingiva form?
soft tissue wall
T or F:
free gingiva tissues meets the tooth in a thin, rounded edge called the gingival margin
true
what type of tissue makes up the free gingiva?
keratinized stratified squamous epithelium
T or F:
the gingival margin does not follow the contours of the teeth
false:
it follows the contours of the teeth, creating a wavy outline
what are the two gingival biotypes?
compare thin vs thick gingival biotypes
thin biotype:
- 1/3 sample, females
- slender teeth
- narrow zone of KG
thick biotype
- 2/3 sample
- quadratic teeth
- wide zone of KG
what is the gingival sulcus?
the space between the free gingiva and tooth surface
what are 4 characteristics of the gingival sulcus?
- V-shaped shallow space around the tooth
- clinically normal sulcus is 1-3 mm as measured by a probe
- base of sulcus is formed by junctional epithelium
- wall of sulcus is non-keratinized
is the inner wall of the gingival sulcus (sulcular epithelium) keratinized or non-keratinized?
non-keratinized, and has a semipermeable membrane
in a healthy individual, where is the base of the gingival sulcus? …for an individual with inflammation?
- in a healthy individual, the base of the sulcus is the coronal aspect of the junctional epithelium; the JE is attached to the enamel
- in an individual with inflammation, the JE will likely be detached from the epithelium, so the base of the sulcus will be deeper
what are 4 functions of gingival crevicular fluid (GCF)?
- cleanses the gingival sulcus
- aids in adhesion of the epithelium to the tooth
- possesses antimicrobial properties
- exerts antibody activity in defense of the gingiva
in a clinically healthy gingival crevice, the resident bacterial plaque results in what? …what does this create?
- the accumulation of high molecular weight molecules
- these molecules permate the intercellular regions of the epithelium, but are limited to the basement membrane
- creates osmotic pressure, drawing fluid from CT into the sulcus; this is the gingival crevicular fluid
describe how gingival crevicular fluid is a transudate of interstitial fluid
- GCF represents the interstitial fluid, which appears in the crevise as a result of an osmotic gradient
- this pre-inflammatory fluid is transudate
- on stimulation, it becomes inflammatory exudate
T or F:
in methods of collection of gingival crevicular fluid, more intracrevicular fluid is collected than extracrevicular fluid
false:
more extracrevicular fluid is collected
name 4 methods of collection of gingival crevicular fluid
- intracrevicular washings
- absorbing paper strips
- twisted threads
- micropipettes
what is a periotron?
an eletrical method devised for measuring gingival fluid absorbed on paper strips
gingival crevicular fluid is composed of enzymatic and non-enzymatic components. name the components of each.
enzymatic components
- host derived and other products
- bacteria derived
non-enzymatic components
- cellular component
- electrolytes
- organic component
name the 10 host derived enzymes that GCF is composed of
- acid phosphates
- alkaline phosphates
- alpha-1 antitrypsin
- arylsulphatase
- aspartate aminotransferase
- B-glucuronidase
- cathetpsin D, G
- matrix metalloproteins
- elastase
- plasminogen activators
name the 7 bacteria derived enzymes GCF is composed of
- acid phosphatase
- alkaline phosphatase
- collagenase
- hyaluronidase
- phospholipase-C
- phospholipase-A
- bacterial proteinases (endo and exopeptidases)
name the 3 cellular components found in GCF
- bacteria
- desquamated epithelial cells
- leukocytes (PMNs, lymphocytes, and monocytes) which migrate through the sulcular epithelium
name the 5 electrolytes of the GCF
- potassium
- sodium
- calcium
- magnesium
- fluoride
with inflammation, there is a positive correlation between [Ca] and [Na] and the Na/K ratio
what 2 organic compounds are found in GCF?
- glucose hexosamine
- hexuronic acid
T or F:
- glucose concentration in GCF is 3-4x lower than that in serum
- result of metabolic activity of adjacent tissues and the local microbial flora
false:
it is 3-4x higher than that in serum
what are the 6 metabolic end products produced as a result of the metabolic activity of adjacent tissues and local microbial flora?
- lactic acid
- urea
- hydroxyproline
- endotoxins
- cytotoxic substances
- hydrogen sulphide
what is the role of cytokines in GCF?
- they are potent local mediators of inflammation
- in GCF, they have been investigated as potential diagnostic markers for periodontal diseases
which cytokines have been investigated as potential diagnostic markers for periodontal disease?
- interleukin 1 alpha and beta
- interleukin 6 and 8
- tumor necrosis factor alpha (TNF-alpha)
- IL-1 alpha and beta have pro-inflammatory effects and defending on a variety of factors, can stimulate either bone resorption or formation
what is prostaglandin E2?
- PGE2 is a product of the cyclooxegnase pathway
- elevated levels in GCF found in patients with periodontitis compared to those with gingivitis
- PGE2 levels are 3x higher in patients with LAP compared to adult periodontitis
what are the normal characteristics of attached gingiva?
- color is pale or coral pink
- may be pigmented; more frequent in dark-skinned individuals; color ranges from light brown to black
what are functions of the attached gingiva?
- allows gingival tissue to withstand mechanical forces
- prevents free gingiva from being pulled away from tooth
what are normal clinical characteristics of the facial attached gingiva?
- texture in health is stippled but determined by genetics
- dense CT fibers attach gingival tissue to cementum and bone
what are the maxillary and mandibular average widths of normal facial attached gingiva?
- maxillary incisors - 3.5-4.4mm; premolars - 1.9mm
- mandibular incisors - 3.3-3.9mm; premolars - 1.8mm
- areas with smaller zones are more susceptible to periodontal issues; more common in the gingiva of the mandible
T or F:
the entire palate is attached tissue
true
with the exception of the free gingiva
where is interdental gingiva/papilla?
it is found in the space between the teeth
name 3 factors that largely determine gingival shapes
- relationship to teeth (crowns)
- genetics
- state of health
what is black triangle disease?
a small black triangle seen between the teeth that is present as a result of the papilla not making contact with the contact point of the teeth
what is the effect of crowding on papilla shape?
it makes it difficult to maintain
T or F:
if there is no contact between teeth, there can still be a papilla
false:
no contact, no papilla
What is the function of the Col?
it connects facial and lingual papillae
what are 3 characteristics of the Col?
- depression between facial and lingual interdental gingiva
- center is not keratinized
- more susceptible to disease
what different groups make up the Col?
- dentogingival grou
- circular group
- dentoperiosteal group
- alveologingival group
T or F:
the Col area is normally not keratinized, even if there is no contact point between the teeth (ie. no papilla)
false:
in Col areas where there is no papilla, it is keratinized
what are 3 characteristics of the junctional epithelium?
- it is continuous with sulcular epithelium
- it completely encircles the tooth
- on enamel and apically extends onto the CEJ
what tissue precedes junctional epithelium during development?
reduced enamel epithelium
describe the formation of the junctional epithelium during development
- reduced enamel epithelium is rapidly replaced with squamous epithelial cells once tooth erupts
- transformed reduced enamel epithelium and oral epithelium form dentogingival junction and junctional epithelium
- final conversion of REE to JE may not occur until 3-4 years post eruption
describe the 2 layers of the junctional epithelium
internal basal lamina attaches to enamel
- lamina densa
- lamina lucida
- hemidesmosomes
external basal lamina attaches to CT
- lamina densa
- lamina lucida
- hemidesmosomes
what is the dentinogingival unit?
the functional unit of junctional epithelium that is reinforced by collagenous fibers in the marginal gingiva
describe the length of the JE
- it varies according to stage of eruption
- Tooth first erupts – most of enamel covered by JE
- Tooth reaches occlusal plane – ¼ enamel surface covered
- Eventually JE lies close to CE junction
- Older patients with root exposure (passive eruption or disease) JE proliferates apically - firm attachment with cementum
describe the lamina propria of gingiva
good vasculature and source of nutrient to JE and source of GCF
T or F:
the JE is impermeable; tissue and cells cannot pass into GCF
false:
it is permeable, and tissue and cells can pass into GCF
describe the rate of turnover of the JE
- very rapid
- epithelial cells migrate coronally and shed into oral cavity via gingival crevice
- rate of turnover dependent on demands placed on tissue; directly related to degree of inflammation
T or F:
the JE has an attachment role and protective role, and it helps maintain integrity of the tooth and periodontium structure
true
describe the permeability of the JE with respect to disease processes
the permeability of the JE allows GCF and defense cells to pass across to protect underlying tissues from disease processes
describe how the JE and GCF are good indicators for severity of periodontal disease
-may contain neutrophils and other inflammatory cells indicating disease and state of health of periodontium
describe the 2 distinct layers of the lamina propria of the gingival CT
papillary layer
- forms finger-like extensions in the depressions delineated by the rete ridges
reticular layer
- located beneath the rete ridges
what are the 3 major gingival fiber groups?
- gingivodental group
- circular group
- transseptal group
*they are primarily composed of type I collagen
what are the 6 minor gingival fiber groups?
- semicircular
- transgingival
- periosteogingival
- interpapillary
- intercircular
- intergingival
what are the cellular elements of gingival CT?
- cells make up 5% of gingival CT
- fibers make up 65% of gingival CT
- remainder is composed of proteoglycans, glycoproteins, and CT ground substance
name the 13 cellular elements in gingival CT
- fibroblasts
- osteoblasts
- chondroblasts
- chondrocytes
- epithelial cells
- mast cells
- adipose cells
- fixed macrophages and histiocytes
- eosinophils
- neutrophils
- lymphocytes
- plasma cells
- PMNs
name the fibrillar elements in the gingival CT
collagen approx 60%
- type I (majority)
- type III (reticular)
elastic fibers
oxytalan fibers
ground substance
- highly hydrated, gel-like
- surrounds fibers
about how wide the the PDL?
0.25mm
what is the attachment apparatus?
PDL + cementum + alveolar bone
name the 5 funcitons of the periodontal ligament
- suspends and maintains tooth in socket
- provides pressure and pain sensory feeling to tooth
- provides nutrients to cementum and bone
- builds and maintains cementum and alveolar bone of tooth socket
- remodels alveolar bone in response to pressure
describe the collagen and elastic fibers of the PDL
collagen fibers
- principle fibers
- intermediate plexus fibers
- sharpey’s fibers
- indifferent fiber plexus
elastic fibers
- oxytalan fibers
describe the statistical characteristics of the PDL
- varies in thickness: 0.1-0.25mm
- widest during heavy occlusion, thinner in nonfunctional teeth
- surface area of socket wall: 150-275sq mm in single root, and 450 for multirooted
- 2000/sq mm in non-functional, and 28,000 in functional
- diameter 2-3 micro m at eruption, double in fully functional teeth
- fiber bundles larger and less numerous on the bone surface than on cemental surface
what is the organization of the PDL fibers?
- transseptal group
- alveolar crest group
- horizontal group
- oblique group
- apical group
- interradicular group
name the 5 CT cells that make up part of the cellular elements of the PDL
- fibroblasts
- cementoblasts
- cementoclases
- osteoblasts
- osteoclases
name the epithelial rest cells that make up the cellular elements of the PDL
rest cells of Malassez
name the defense cells that make up the cellular elements of the PDL
- mast cells
- macrophages
T or F:
neurovascular elements form part of the ground substance of the PDL
false:
they form part of the cellular elements of the PDL
does the cementum have its own blood/nutrient supply?
no
the cementum is bone-like. is it more or less resistant to resorption than bone?
more resistant
what is the cementum?
- thin layer of hard, mineralized tissue that covers the surface of the root
- light yellow
- overlies dentin
what is primary cementum? secondary cementum?
- primary cementum is acellular cementum
- secondary cementum is cellular cementum
describe the 3 cementoenamel junction relationships
- cementum overlaps enamel: 60-65%
- cementum does not meet enamel (gap): 5-10%
- cementum meets enamel at a butt joint: 30%
describe characteristics of bone
- surrounds and supports roots of teeth in upper and lower jaw
- existence of alveolar bone is dependent on presence of teeth: extractions lead to bone resorption
name 4 types of bone
- alveolar bone proper (cribriform plate)
- cortical bone
- cancellous bone
- periosteum (vascular)
describe the alveolar bone proper
- alveolus: bony socket that houses the root of the tooth
- large pores where blood vessels connect structures
- ends of PDL fibers are embedded in alveolar bone proper
describe characteristics of cortical bone
- layer of compact bone that forms hard outside wall of jaws on facial and lingual
- surrounds alveolar bone proper and gives support to socket
- thinnest in incisor, canin, premolar area and thickest in molars
- does not show up on radiographs
- alveolar crest most coronal portion
describe characteristics of cancellous bones
- spongy, lattice-like bone filler between cortical bone and alveolar bone proper
- oriented around tooth to form support for alveolar bone proper
describe characteristics of the periostium
- layer of connective soft tissue covering outer surface of bones
- collagenous tissues and an inner layer of elastic fibers
describe the vascular supply and innervation of the PDL
- vascular supply enters from three sources: apical vessels, penetration through the alveolar bone, anastamosis from the gingiva
- lymphatic vessels
- nerves
